Breast cancer is one of the few major illnesses for which physicians may not recommend a specific treatment option. North American women are more likely to opt for precautionary breast surgery when physicians do not specifically counsel against it, according to a new study. This research was presented at the American Society of Breast Surgeons Annual Meeting, in Las Vegas, Nevada. The research also demonstrates how clarity during consultations and the capability of clinical facilities also play important roles influencing a woman's breast cancer treatment choices.

This study looked at cases where cancer was diagnosed in only one breast. The form of prophylactic surgery known as a contralateral prophylactic mastectomy entails removing the healthy breast at the same time as the cancerous breast. The procedure can reduce the risk of breast cancer recurrence in women who have a strong family history of breast or ovarian cancers and in women who have a genetic mutation that makes breast cancer more likely.

"While effective for such groups, the number of prophylactic mastectomies across North America has risen among women without these underlying conditions—among women who have only an average risk of developing cancer in their noncancerous breast." explained lead author Andrea Covelli, MD, a University of Toronto general surgery resident at St. Michael's Hospital in Toronto, Ontario, Canada.

Previous national studies have shown that instances of prophylactic breast surgery among women with early-stage breast cancer at average-risk for recurrence have increased nearly twelvefold in the United States over the last decade. In Canada, rates increased by 140% between 2008 and 2010.

Covelli interviewed 45 surgeons in North America to identify factors that determine the course of treatment.

In the United States, some states legislate that surgeons present all treatment options to patients. The research found that surgeons in the 20 states with such legislation complied with the law, but generally surgeons did not recommend one procedure over another. Instead, they encouraged patient choice. Canadian surgeons discussed similar surgical options with their patients. However, they more often specifically recommended breast-conserving surgery and counseled against prophylactic mastectomies.

"We learned that surgeon's recommendations and detailed consultations influenced women's decisions for breast cancer treatment," said Covelli. "Consultations were especially important when it came to MRI findings. When MRI results were presented without detailed explanations, women were more likely to opt for prophylactic mastectomies."

If women were being treated at health care facilities with access to immediate reconstruction, they were also more likely to choose prophylactic surgery.

Immediate reconstruction was associated with the choice of prophylactic mastectomy and is more widely available in the United States than in Canada. In both countries, many patients requested a prophylactic mastectomy after returning from a consult with a reconstructive surgeon.

"We need to look at what happens during that consult to better understand patient decision-making," said Covelli. "Patients should ask for their doctor's opinion if helpful to them. Most surgeons have years of experience treating breast cancer and can provide valuable counsel and advice."